Refrigerating apparatus



Patented Junell, 1946 REFRIGERATIN G APPARATUS Lawrence A. Philipp, Detroit, Mich, assignor to Nash-Kelvlnator Corporation, Detroit, Mich., a corporation of Maryland Application May 29, 1944, Serial No. 537,809

2 Claims.

This invention relates to refrigerating apparatus and more particularly to an improved evaporator for -use in household refrigerators.

I have foundthat a highly efficient refrigerant evaporator may be economically formed of extruded metal stock bent to provide a U-shaped receptacle to receive articles to be frozen and having spaced headers positioned at opposite ends of the extruded member. The spaced headers are connected to the interconnected compressor and condenser elements to complete the refrigerating cycle.

An object of this invention is to provide an improved evaporator having spaced apart headers uniform suction from a coinpresser unit posi-- tioned in the refrigerator circuit.

Yet a further object is to provide an extruded evaporator having .a' plurality of parallel fluid passages surrounding a freezing compartment, and communicating with spaced headers connected to a refrigerating circuit insuch a manner that substantially-uniform pressures and liquid refrigerantlevels are maintained in both headers.

Still another object of the invention resides in the provision of an improved evaporator capable of efficient operation and which may be economically manufactured.

Other objects and advantages of this invention will be apparent from the following detailed description considered in connection with the accompanying drawing, submitted for purposes of illustration only and not intended to define the scope of the invention, reference being had for that purpose to the subjoined claims.

In the drawing, wherein similar reference characters refer to similar parts throughout the several views:

Fig. 1 is a diagrammatic view illustrating a refrigerating circuit embodying the present inven tion: 1

Fig. 2 is a sectional view taken substantially on the line 2-2 of Fig. 1, looking in the direction of the arrows; and

Fig. 3 is a side elevation partly in section of my improved evaporator. i

Before explaining in detail the present invention, it is to be understood that the invention is not limited in its application to the details of construction and'arrangement of parts illustrated 5 in the accompanying drawing, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminolog employed herein is for the purpose of description and not of limitation.

Referring now more particularly to Fig. 1, a refrigerating circuit is formed by a motor compressor unit ill, a condenser element I2 and a refrigerant evaporator l4.

The evaporator it consists of an extruded body portion it having a plurality of spaced parallel passageways II. The extruded body portion i8 is contoured to provide a substantially U-shaped receptacle as illustrated in Fig. 1 having vertically extruded walls and 22 closed at the bottom by a horizontally disposed wall 24. A shelf 26 may be secured to the vertically extended walls 20 and 22 to provide a support for ice trays or other articles to be frozen. The bottom wall 24 may also 25 be used as a support for articles to be frozen.

The vertically extended walls and 22 are provided at their tops with horizontally disposed headers 28 and 30, respectively. The spaces within the headers 28 and 30 are interconnected with each other through the parallel passageways it formed in the extruded body portion Th header 30 is connected by way of a conduit 32 with the inlet side of the motor compressor unit Ill whereby gaseous refrigerant may be withdrawn from the evaporator l4 and recompressed in the motor compressor unit l0.

Compressed gaseous refrigerant is discharged from the motor compressor unit l0 through a conduit ll connected with a condenser coil 36 having heat radiating fins 38 secured thereto to form the condenser i2. Heat is absorbed from I the gaseous refrigerant in the condenser coil 86 by the heat radiating fins, and the gaseous refrigerant is liquifled adjacent the bottom of the condenser l2.

Liquid refrigerant from the condenser l2 passes through a strainer 40 and into a metering conduit 42 of small diameter communicating with the header 28 of the evaporator ii to direct liquid refrigerant to the evaporator to complete the refrigerating cycle. I

As-illustrated in Fig. 3 a small tube 44 positioned in one of the extruded passages i8 projects into the header 28 above the liquid level on 46 therein to permit gaseousrefrigerant from the header :0 to pass through the liquid refrigerant in the parallel passageway I8 to maintain substantially equal -fluid pressures in the headers 28 and 88 and to maintain the level of the liquid refrigerant substantially uniform in both headers. As shown the tube 44 is relatively short compared with the length of passageway i8. Also, as shown, engages the inner surface of tube l8. It will also be noted that the inlet part of tube 44 isentirely above the liquid level 48, in header 28. In the operation of this invention as theliquid refrigerant absorbs heat from the evaporator it is converted into gaseous form and rises to the space within the headers 28 and 88 above the liquid level 88 therein. The motor compressor i8 withdraws gaseous refrigerant from the header 80 and liquid refrigerant is supplied to the header 28 from the condenser l2.

The tube 44 projecting into the space above the liquid level 46 in the header 28 breaks the pressure lock causedby all of the passageways l8 terminating at the same level and permits gaseous refrigerant to boilthrough the liquid refrigerant in the passageway 18 having the tube 48 positioned therein to maintain substantially equal fluid pressure in both of the headers 28 and 88.- Gaseous refrigerant from the header 28 passes through the passageway l8 having the tube 84 positioned therein under the influence of sue.-

tion exerted by the motor compressor unit III- through the header I8, and the level of the liquid refrigerant in the headers 28 and 30 is .maintained substantially uniform.

Although only a preferred form of the inven- 4 tion has been illustrated, and that form described in detail, it will be apparent to those v skilled in the art that various modifications may the outer surface of tube 88 be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. In a refrigerator having refrigerant evaporator, compressor and condenser elements, the evaporator comprising a substantially U-shaped extruded member having a plurality of spaced parallel passages, spaced headers positioned at opposite ends of'said parallel passages, connecting means'between one of the headers and the compressor, connecting means between the other of the headers and the condenser, and pressure equalizing means between said headers comprising a tube of lesser length than said passage positioned in one of said parallel passages and projecting into'its associated header with its entire inlet end being above the liquid level therein.

2. An evaporator for refrigerating apparatus comprising a sheet of extruded metal stock bent to form a substantially U-shaped member to receive articles to be refrigerated and having a plurality of spaced parallel passages, spaced headers positioned at opposite ends of the 'extruded sheet with the passages communicatin with the headers below the liquid level therein. and a tube extending partway into one of said passages and upwardly with its inlet end being positioned above the liquid level in one of said headers for receiving refrigerant gas only from above the level of liquid in said header.

LAWRENCE A. PIiILlPP. 

